Spray nozzle



June 3, 1969 R. c. LAWRENCE, JR 3,447,756

SPRAY NOZZLE Filed Sept. 2,-1966 I N VEN TOR. Iowa/v0; I2

Power 6 United States Patent 3,447,756 SPRAY NOZZLE Robert C. Lawrence,Jr., 1943 Barrington Court, Claremont, Calif. 91711 Filed Sept. 2, 1966,Ser. No. 576,897 Int. Cl. Bb 1/04, ]/20 US. Cl. 239-594 4 ClaimsABSTRACT OF THE DISCLOSURE This invention relates generally to spraynozzles; more particularly, the present invention relates to a spraynozzle having an improved fiat fan-shaped spray pattern characterized bygenerally uniform fluid velocity and coverage over its entirecross-sectional and immunity to change in the spray pattern with nozzlewear.

As will appear from the ensuing description, the present spray nozzlemay be used to advantage in various applications, particularlyindustrial applications. However, the nozzle is intended primarily forremoving surface material from a work member, such as bark from treesand scale from metal plates. The invention will be described inconnection with this latter application.

It is common practice in steel rolling mills to remove scale from steelplate by directing high velocity water sprays against the surfaces ofthe plate. A typical scale removal system of this kind, for example,comprises means for transporting the plate edgewise between sets ofdescaling nozzles which direct high velocity water sprays againstoposite sides of the plate. The ideal nozzle for this purpose has agenerally flat fan-shaped spray pattern. A variety of such descalingspray nozzles have been devised. The existing nozzles, however, are nottotally satisfactory.

Thus, the existing nozzles are deficient in that the effective impactforce of the spray against the work plate varies substantially over thecross-section of the spray pattern. This is due to the fact that thevelocity and/or effective coverage of the water in the spray varies fromone point to another over the cross-section of the spray.'As a result,the existing descaling nozzles do not produce a uniform descalingaction. Owing to the high velocity flow of water through descalingnozzles, the latter tend to wear in use. Another defect of the existingscale nozzles resides in the fact that their spray pattern changesappreciably with such wear. The nozzles must therefore be periodicallyadjusted or replaced. This necessitates shut-down of the rolling milland thus involves substantial cost, production delay, and inconvenience.

It is evident at this point that a definite need exists for an improveddescaling nozzle which is not subject to the noted deficiencies of theexisting nozzles. The present invention provides such an improveddescaling nozzle. As will appear from the ensuing description, however,the improved nozzle of the invention is not limited in usefulness tothis metal plate descaling application although the invention, asalready noted, will be described in this connection.

One important object of the present invention, then, is to provide aspray nozzle having an improved spray pattern characterized byrelatively uniform impact force over substantially its entirecross-section.

A related object of the invention is to provide a spray 3,447,756Patented June 3, 1969 ice nozzle of the character described having agenerally flat fan-shaped spray pattern which is ideal for metal platedescaling use and effects a relatively uniform descaling action.

Another important object of the invention is to provide a spray nozzleof the character described whose spray pattern does not change withnozzle wear occasioned by high velocity fluid flow through the nozzle.

A further object of the invention is to provide a spray nozzle of thecharacter described which may be readily reconditioned, when necessary.

Yet a further object of the invention is to provide a spray nozzle ofthe character described which is relatively simple in construction,economical to manufacture, and otherwise ideally suited to its intendedpurposes.

Other objects, features and advantages of the present invention willbecome apparent to those versed in the art from a consideration of thefollowing description, the appended claims and the accompanyingdrawings, where- 1n:

FIGURE 1 is a perspective view of a metal plate rolling machine havingplate descaling means embodying improved descaling nozzles according tothe invention;

FIGURE 2 is an enlarged side elevation, partly in section, of one of thedescaling nozzles shown in FIG- URE 1;

FIGURE 3 is a front end view of the nozzle taken on line 3-3 in FIGURE2;

FIGURE 4 is an enlarged section taken on line 4-4 in FIGURE 3;

FIGURE 5 is a section taken on line 55 in FIG- URE 4;

FIGURE 6 is a perspective view, on reduced scale, of a front end of thenozzle and illustrates the improved fan-shaped spray pattern of thenozzle;

FIGURE 7 is a section taken on line 77 in FIG- URE 5; and

FIGURE 8 is a perspective view, on reduced scale, of one-half of a splitnozzle tip embodied in the present spray nozzle.

In FIGURE 1 of these drawings, there is illustrated a metal platerolling machine 10 which is typical of those employed in steel rollingmills for rolling steel billets into plate. Rolling machine 10 includesrolls 12 which serve to form and feed edgewise the metal plate 14produced by the machine. At the outfeed end of the rolling machine is adescaling station 16 having descaling means 17 for removing surfacescale from the plate 14.

Descaling means 17 comprise upper and lower water headers or manifolds18 which are mounted on the machine frame 20 above and below the path ofmovement of the metal plate 14 through the machine. Each header 17 has anumber of descaling spray nozzles 22 for directing high velocity waterspray against the adjacent surface of the plate 14. The nozzles haveoverlapping spray patterns, as shown, whereby, ideally, the entiresurface area of each side of the plate is cleaned or descaled during itspassage through the descaling station 16. As noted earlier, however, theexisting descaling spray nozzles for this purpose are defective in thatthey do not produce a uniform descaling action, owing to the lack ofuniformity of the impact force of the spray from the nozzles over theentire cross-section of the spray. Moreover, the existing nozzlesrequire periodic adjustment or replacement, owing to the change in theirspray pattern with nozzle wear, which necessitates shut down of therolling mill. The present invention is concerned with the improvedconstruction of the descaling spray nozzles 22, whereby these defects ofthe prior art nozzles are avoided.

As shown in FIGURES 2 through 8, the present spray or descaling nozzle22 has an outer body 24 with a threaded rear end 26, a threaded frontend 28, and an intervening polygonal wrench receiving portion 30.Extending axially through the body is a bore 32, the front end of whichis counterbored at 34. Within the body is a tubular strainer 36. Thisstrainer comprises a sleeve 38 which fits slidably within the body bore32 and extends though the open rear end of this bore to a positionrearwardly of the nozzle body 24. The forward end of the strainer sleeve38 extends through and a short distance beyond the forward end of thebody counterbore 34. Adjacent the front end of the strainer sleeve is anexternal circumferential shoulder 40 which seats rearwardly against theinternal annular shoulder 42 which is defined on the nozzle body 24 atthe rear or inner end of the body counterbore 34.

Extending axially through the strainer sleeve 38 is a water passage 44.The rear end of this passage opens radially to the outside of the sleevethrough a number of entrance slits 46 in the rear extending end of thesleeve. Duringoperation of the nozzle 10, water enters the nozzlethrough the strainer slits 46 and flows forwardly through the strainerpassage 44. The strainer entrance slits 46 serve to strain or filter outparticulate matter in the water stream, thus to prevent blockage of thenozzle by such matter. The forward end of the strainer passage 44 opensthrough the forward end of the strainer sleeve 38.

As shown best in FIGURE 2, the wall of the nozzle body counterbore 34 isradially spaced from the forward end of the strainer sleeve 38, thus todefine an annular space therebetween. Surrounding the forward end of thestrainer sleeve, within this space, and extending forwardly beyond thesleeve is a collet sleeve 48. The rear end of this collet sleeve isexternally cylindrically shaped to fit slidably in the nozzle bodycounterbore 34. The collet sleeve is sealed to the wall of thecounterbore by an O- ring 50. Extending through the collet sleeve is aforwardly converging conical collet bore 52, the rear end of whichreceives the forward end of the strainer sleeve 38. The strainer sleeveis sealed to the wall of the collet bore by an O-ring 54. Collet sleeve48 has a forwardly presented annular shoulder 56 about its forward end,forwardly of the nozzle body 24.

Threaded on the forward end of the nozzle body 24 is a nut 58 having apolygonal wrench receiving portion 60. At the front end of the nut is aninwardly directed flange 62 which seats rearwardly against the colletsleeve shoul der S6. Accordinglly, the nut may be tightened to urge thecollet sleeve rearwardly against the strainer shoulder 40, thereby toretain the nozzle body 24, strainer 36, and collet sleeve 48 inassembled relation.

The present invention is concerned primarily with a nozzle tip 64 whichis positioned in the front or outer end of the collet bore 52. Thisnozzle tip is externally conically tapered to complement the taperedcollet bore 52. The rear or inner end face of the nozzle tip seatsagainst the front or outer end face of the strainer sleeve 38.Accordingly, when the nozzle nut 58 is tightened, as mentioned earlier,the nozzle tip 64 is urged forwardly in the collet bore 52 and isthereby wedged tightly in. this bore to preclude water leakage betweenthe wall of the bore and the outer surface of the tip. For reasons whichwill be explained presently, the tip is preferably split into two matinghalves 64a, 6417 along a parting plane containing the central axis ofthe tip.

Extending axially through the tip is an orifice 66 having a rear orinner entrance end 68 and a front or outer exit end 70. The orifice hasa generally rectangular shape in transverse cross-section and is boundedat two opposite sides by side walls 72 and at its remaining sides byedge walls 74. As shown in FIGURE 4, the orifice edge walls 74 divergetoward the front end of the tip, thus providing the orifice with arelatively wide forwardly diverging tapered cross-section, in everyplane parallel to the parting plane between the nozzle tip halves orsections 64a,

4 6411. As shown in FIGURE 5, the orifice side walls 72 converge towardthe parting plane over the major portion of their axial length and thenextend parallel to this plane, thus to provide the orifice with arelatively narrow forwardly converging tapered cross-section in everyplane parallel to the orifice axis and normal to the parting plane.

It is significant to note at this point that both the entrance tip oropening 68 and the exit end or opening of the orifice 66 are rectangularin shape and parallel one another. The diameter of the strainer passage44 is substantially greater than the major or lengthwise dimension ofthe entrance opening 68. The exit opening 70 has the narrow slit shapebest illustrated in FIGURES 3 and 6.

The nozzle tip 64 is preferably split, as described, earlier, tofacilitate manufacture of the tip. Thus, the orifice '66 can beconveniently and economically machined by simply milling appropriatelyshaped grooves in the confronting surfaces of the tip sections 64a, 64b,such that when the tips are assembled in the nozzle, the milled groovesdefine the orifice. FIGURE 8 best illustrates the milled groove inone-half of the nozzle tip.

In use, a number of the present nozzles 10 are threaded in the headers18 in FIGURE 1 in such a way that the nozzle orifices 66 open toward thepath of movement of the metal plate 1-4 between the headers. The headersare supplied with water under high pressure through an inlet line 76.The water emerges from each nozzle in the form of a fan-shaped spray 78,shown in FIGURE 6. The several nozzles embodied in the descaling means17 are oriented and spaced along the headers 18 in such a Way that thewater sprays 78 from the nozzles are located in a common planecontaining the headers and the sprays from adjacent nozzles overlap oneanother, in the manner illustrated in FIGURE 1.

It has been found that the spray pattern of the present nozzle isunique, and produces a superior descaling action, for the reason thatthe water velocity and coverage is essentially uniform throughout thecross-section of the spray. This results in relatively uniform impactforce of the water against the plate 14 at every point throughout thespray from each nozzle. These superior characteristics of the spray 78from the present nozzle 10 is due, in part, to the unique taperedconfiguration of the nozzle orifice 66 shown in FIGURES 4 and 5, and inpart to the fact that both the orifice inlet 68 and outlet 70 arerectangular in shape. It is believed that this rectangular shape of theorifice inlet and outlet is the primary factor which yields the superiorspray characteristics of the nozzle. The precise reasons why theillustrated orifice configuration yields this superior spray pattern arenot understood. However, that the illustrated orifice configurationdoes, in fact, yield such a superior spray pattern has been clearlydemonstrated by extensive experimental use of a number of the presentnozzles for descaling steel plate in a steel rolling mill. Accordingly,it is evident that the invention herein described and illustrated isfully capable of attaining the several objects and advantagespreliminarily set forth. It is now evident, of course, that, as notedearlier, the present spray nozzle is not limited in usefulness to suchdescaling applications.

Although a specific embodiment of the present invention has beenillustrated and described herein, it will be understood that the same ismerely exemplary of presently preferred embodiments capable of attainingthe objects and advantages hereinbefore mentioned, and that theinvention is not limited thereto; variations will be readily apparent tothose versed in the art, and the invention is entitled to the broadestinterpretation within the terms of the appended claims.

The inventor claims:

1. A nozzle comprising:

a generally tubular body having externally threaded front and rear ends,

there being a bore extending axially through said body and terminatingat the front end of said body in a counterbore opening through saidfront end,

a collet sleeve having a rear end slidably positioned in saidcounterbore and a front forwardly presented external circumferentialshoulder,

a nut threaded on the front end of said body including a forwardinwardly directed flange seating rearwardly against said collet sleeveshoulder,

said collet sleeve having a forwardly extending, coni cally taperedcollet bore extending therethrough,

an externally conically tapered nozzle tip positioned in said colletbore, and

said nozzle tip having an orifice extending axially therethrough, saidorifice having a relatively narrow rectangular shape and terminating atits rear end in a rectangular entrance opening and its front end in arectangular exit opening, said orifice being bounded at two oppositesides by planar side walls having major planar portions which convergein the direction of said exit opening and at its remaining sides byplanar edge walls which diverge in the direction of said exit opening.

2. A nozzle according to claim 1 wherein:

said orifice side walls have minor planar portions immediately adjacentsaid exit opening which generally parallel said axis.

3. A nozzle according to claim 1 wherein:

said nozzle tip is split into two mating halves along a parting planecontaining said axis and the major longitudinal axes of said entranceand exit openings, and

said nozzle includes internal forwardly presented shoulder means seatingagainst the rear end of said nozzle tip.

4. A nozzle comprising:

a tubular body having a fluid passage extending longitudinallytherethrough,

a nozzle tip at one end of said body having an inner end face extendingacross the adjacent end of said passage and an opposite outer end face,

said nozzle tip containing an orifice or rectangular cross-section fromend to end extending through the tip on the central axis of saidpassage,

said orifice having a rectangular entrance end opening through saidinner nozzle tip face to said passage and a rectangular exit end openingthrough said outer nozzle tip face,

said orifice being bounded at two opposite sides by planar wide wallshaving major portions which converge in the direction of said exit endand at its remaining sides by planar edge walls which diverge in thedirection of said exit,

said entrance end of said orifice defining a rectangular entranceopening to said orifice having a major length dimension and a minorwidth dimension, and

the diameter of said passage at said inner nozzle tip face beingsubstantially greater than said major dimension of said orifice entranceopening.

References Cited UNITED STATES PATENTS 1,133,711 3/1915 Cornelius 2395951,889,201 11/1932 Holveck 239597 2,969,190 1/1961 Foreman 239-6013,101,906 8/1963 Webber 239--592 3,273,805 9/1966 Hall 2.39-592 EVERETTW. KIRBY, Primary Examiner.

US. Cl. X.R.

